Roman Harbour

 seaport, Roman Empire

The Harbour at Caesarea was built by King Herod between 22 BC and 9 BC. It was one of the greatest engineering wonders of its time. It was the first major construction project to use concrete that would set under water. The length of the southern break water is 500 metres (1,600 ft). The length of the northern break water is 200 metres (660 ft). The largest stone block measures 5.5 metres (18 ft) by 1.25 metres (4.1 ft) by 1.25 meters (over 20 short tons (18 t)). The largest concrete block measures 11.5 meters by 15 metres (49 ft) by 2.4 metres (7.9 ft). The concrete blocks were created by floating a form on the water and filling it with concrete, as it filled up it would sink into place and the concrete would set under water.

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